Hackers Force French Supermarket Fridges to 50°C in Major Cyber Attack

Hackers have targeted hundreds of supermarkets across France in a large-scale cyber attack, remotely manipulating refrigeration systems to raise temperatures to as high as 50°C. The incident has resulted in significant food losses and reports of fires, prompting a national investigation into the security of connected refrigeration equipment.

The attack, which began overnight on Sunday 11th October 2026, affected several major supermarket chains, including Intermarché, Carrefour and Coopérative U. Retailers have been forced to discard fresh and frozen food after refrigeration systems were compromised, raising concerns about the potential impact of cyber attacks on essential retail infrastructure.

Hundreds of stores affected

Intermarché’s parent company, Les Mousquetaires, reported that around 150 of its stores had been affected, with some refrigeration units reaching temperatures of 50°C for approximately six hours. The company said affected food stocks had to be thrown away to avoid potential food safety risks.

Carrefour also confirmed that around 80 of its supermarkets were impacted, while Coopérative U reported disruption across its network. Other retailers have been mentioned in reports about the incident, although the full extent of the damage remains under investigation.

The attack appears to have exploited connected refrigeration management systems, allowing attackers to interfere with equipment designed to maintain safe temperatures for perishable products.

In addition to food waste and financial losses, French authorities have reported fires associated with the incident. Investigators are working to establish precisely how the systems were compromised and whether the reported damage is linked to the same attack.

Outdated refrigeration software under scrutiny

Early reports have pointed towards refrigeration control equipment supplied by Danish company Danfoss. According to a source close to French Prime Minister Sébastien Lecornu, France’s National Cybersecurity Agency, ANSSI, identified a vulnerability in software supplied by the company.

Danfoss said affected systems in France were running outdated firmware and reiterated that customers should keep supported systems updated with the latest firmware. The company has acknowledged incidents involving refrigeration management systems in France, although the precise method used by the attackers has not yet been established publicly.

Investigators have not confirmed which vulnerability, if any, was exploited. It would therefore be premature to conclude that outdated firmware alone explains how the attackers gained access.

The incident highlights the risks associated with internet-connected industrial control systems. Refrigeration controllers are designed to regulate temperatures and protect food supplies, but if attackers gain control of them, the consequences can extend well beyond conventional IT disruption.

French government launches investigation

French Prime Minister Sébastien Lecornu has instructed ANSSI to investigate the attack. The Paris prosecutor’s office has also opened an investigation into the large-scale incident, focusing on identifying affected businesses and establishing the links between the cyber attack, food losses and reported fires.

French authorities are also coordinating with European counterparts to determine whether organisations in other countries may have been affected.

Separately, Dutch supermarket operator Ahold Delhaize reported a security incident affecting its network and took several systems offline as a precaution. Its Albert Heijn supermarket app and delivery services were disrupted. However, investigators have not established whether these problems are connected to the French attack.

A warning about attacks on physical infrastructure

The incident demonstrates how cyber criminals can potentially disrupt physical equipment rather than simply steal information, encrypt files or demand a ransom.

Modern supermarkets rely on connected technology to manage refrigeration, heating, ventilation, stock systems and other essential operations. If these systems are inadequately secured, attackers may be able to cause disruption that affects customers, staff, businesses and the wider food supply chain.

The financial consequences could also be substantial. Retailers must account for destroyed stock, equipment inspections, potential repairs and operational disruption. Intermarché has warned that insurance policies may not cover this type of incident.

For businesses operating connected industrial equipment, the attack reinforces the importance of applying security updates, restricting remote access, changing default credentials, separating operational technology from ordinary corporate networks and monitoring systems for unexpected changes.

The investigation remains ongoing, and authorities have yet to publicly establish who was responsible for the attack or confirm the precise vulnerability exploited. The incident is nevertheless a significant reminder that cybersecurity failures can have direct consequences for physical infrastructure and public safety.